- How do I prevent moles and voles from damaging my garden? What are the
- differences between them? Are there any good references available?
Voles and moles are not an uncommon issue in our area and there are steps that can be taken
to minimize their impact. Both are rodents that can be an annoyance to gardeners.
Voles
Voles are mouse-like rodents that use well-traveled above ground runways to connect to burrow openings. Moving mulch or other covering vegetation may reveal these runways in affected areas. Damage to roots of flowering plants and vegetables and girdling damage to small trees or saplings most often have voles as the primary culprit.
The following steps are suggested to effectively deal with voles:
- Modify the habitat by removal of mulch and weeds and heavy vegetation around the garden area of concern. This removes protection for the vole population.
- Barriers exclude voles via physical barrier such as a wire fence ¼ inch or smaller to a height of 12” with the bottom edge buried 6-10 inches to prevent tunneling. This is practical for relatively small areas, but more difficult and costlier for larger areas.
- Baiting: Anticoagulant baits toxic to voles are an option, however, care must be taken to keep household pets and children away from the baits, which require placement in the vole runways in order to be effective. Several applications (3-4) typically are required.
- Trapping, repellents and predators (e.g. the family cat) may have some impact but are generally not as effective unless a very small population of voles exists in your environment. Refer to the references below for additional information.
In summary, the more effective, least impactful to the environment, and lowest risk option is to prevent voles from getting to your plants using barriers and taking away their cover, e.g. taking up mulch and weeding. The following publications contain additional detail regarding voles and methods to prevent them from damaging the garden:
http://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn7439.html
https://ext.vt.edu/lawn-garden/turfandgardentips/tips/mole-vole.html
Moles
Moles, unlike voles, live underground and generally inhabit lawn areas of homeowners, etc. Moles tend to avoid heavy clay or stony soils, since they make tunneling difficult. The types of moles in Virginia and drawings of each are provided in the Virginia Cooperative Extension reference (vt.edu) cited below. The good news is that moles won’t generally eat plants. They are beneficial in many ways because they loosen the soil and eat the larvae of many insect pests such as Japanese Beetles and they are insectivores, subsisting on the likes of grubs and earthworms. They can damage plants by uprooting them when tunneling, so some gardeners dislike them. But generally, they are not a large problem in the garden. They tend to me more of an issue with turf management due to unsightly tunneling mounds created by the burrowing animal. The following options exist for control of moles for the homeowner:
- Barriers may be effective in limiting access to relatively small areas by burying hardware cloth to a depth of 12-15 inches around the perimeter of the area of concern and extending about 5 inches above ground level.
- Trapping should be viewed as only a temporary fix to a mole problem, as unless their food supply they will likely replace themselves. If trapping is to be attempted, the best time to do so is during spring. The process is dealt with in detail at the VT.edu reference below and focuses on the mole runways for placement.
- Fumigants, repellents and toxicants are classified “restricted use only” and can only be applied by certified pesticide applicators. Furthermore, the Virginia Tech documentation suggests that their application is often ineffective in reducing mole activity and damage.
The following publications explain more about moles methods for control:
